Oil composition



Patented Mar. '29, 1938 UNlTED STATESILPATENT OFFICE on. comosmonRaphael-Hosea, Cranford, I i. 1., assignor to Standard Oil DevelopmentCompany, a corporation of Delaware No Drawing. Application July 14,1934, Serial No. 735,202

12 Claims;

absolutely necessary, it is also desirable to produce a finished'oiloflow. oxidation rate. 15 Certain substances have been found which,

when added to lubricating oils in small proporoxidation rate of the oil,and in the present case a new. class of such substances has been dis- 20covered. The present invention relates to the general class of.meta'llo-organic substances in which at least-two metal atoms arepresent in the molecule and linked together according to the followingformula:

, RMNR1 where M and N represent the two metal atoms, the nature of whichwill be specified below, but which may be either the same or differentele- 30 ments, and where R; and R1, represent organic radicals such asalkyl or aryl groups. The subscripts :r and y denote the number of suchradicalsin accordance with the usual chemical nomenclature. Theparticular class of substances may be preparedin any preferred mannerbut ordinarily it is' preferred to make them according to the followinggeneral equation:

in which the symbols have the same general sigwhere M, N and P are themetal atoms and- R has the significance denoted above. These reactionsare. preferably carried out in a solvent comprising 55 liquid ammonia orlow boiling amines and at temtions, have the power of greatly reducingthe v substituted with halogens or sulphur and other elements. 40

peratures below 0., preferably below -20 or -30 0..

The metals which may be used in producing the improved agent generallycomprise those of the 2nd, 3rd, 4th and 5th group of the periodic 5table of-elements, and particularly those of the 2nd or right-handsub-group. In generaliit is found that in any particular group thehefivier han -molecular weightmetals are more effective the lighter.Thus,.in general mercury is ore effective than cadmium or zinc, leadmore (1 able than tin or germanium and bismuth is be ter than arsenic orantimony. As stated above, ere are at least two of the metal atoms inthe molecule of the particular agent and these may be identical or maybe difl'erent. For example, in cases where two metal atoms are present,the agent may contain only lead or tin or it may contain an atom each oflead and tin, or in cases I where three metal atoms are present, tin,lead and antimony may be used.

As to the organic'portion ofthe molecule, it should be understood thatthe number of such groups must depend upon the valance of the particularmetal to which they are attached. Hydrogen may be present in lieu'of,some of the carbon 4 containing groups, but it is preferred that atleast one carbon containing group be present and ordinarily all of thehydrogen is replaced by carbon containing groups which may be similar orwhich may be of the diiferent types to be enumerated below.

The carbon containing .sroups may be allphatic, such as methyl, ethyl,propyl, butyl, amyl or the like, either of straight chain or branchedchain structure as in isopropyl or secondary butyl groups. These groupsmay be purely hydrocarbon as is preferred or they may be,-

. It is generally preferred to-provide at least one aryl group inthe'molecule and among these may be mentioned phenyl, naphthyl and thelike, but the alkylated aryl groups such as cresyl, isopropyl alphanaphthyl and the like may also be used. In addition to these,hydrogenated aryl groups may, of course, be used. The above cyclic groupmay be either purely hydrocarbon or they may contain other elements suchas hydroxyl or amino substituted groups or halogens either atvI vtacheddirectly to'the ring min a side chain'as will be appreciated. I

The efllciency' oftthe particular compounds depends on the particularmetal or metals used and the particular organic groups. When all of 56the organic groups are alkyl, that is to say, allphatic, the compoundsare not very effective until temperatures of 200 to 250 C. are reached,but

when aryl groups are present the compounds generally have .a wider rangeof effectiveness, for example, as low as 150 to 200 C., and up to 250 C.and higher.

The compounds used for the present compositions are those which aresoluble in hydrocarbon oils, at least to the extent necessary forpresent purposes. If a particular combination of metals is found not togive sufliciently soluble products for the best results, it has beenfound that the addition of more alkyl groups or alkyl groups containinga greater number of carbon atoms will increase the solubility to thepoint desired. It is often desirable to add small amounts of benzol ortoluol or their equivalents to dissolve the agents am to cause anintimate dispersion through the oil. If desired the lower molecularweight solvents may be removed by distillation or otherwise.

The amount of the agents used may be quite minute so that it is notnecessary to obtain a high degree of solubility, for example, as littleas .01 to .02% often produces good' effects but it is often desirable touse as high as .1 to .3%, and it is quite rare that more than .5% isrequired.

These materials may be used in a great variety of petroleum products,for example, in lubricating oils and greases obtained from all varietyof crudes such as obtained from parafiin or naphthene base crudes whichhave been refined by the ordinary methods of distillation, acid, alkaliand clay treatment or especially refined by other processes, among whichmay be mentioned hydrogenation, destructive hydrogenation, solventextraction and the like, as well as the heavy acid treatment forproduction of white oils which are used for medicinal and technicalpurposes. These Example 1 Trimethyl triphenyl stannane is preparedaccording to the following equation:

(CH3) aSnNa+ (CsHs) 3SHC1- (CHa) 3Sn-Sn (CsHs) 3 +NaCl Reaction isbrought about by mixing the reactants in equivalent proportions inliquid ammonia and reaction takes place fairly rapidly. To test theeflicacy of. this substance 2% is added to a well refined lubricatingoil of S. A. E. 20 grade. This blend is then compared with a blank, thesame 011 which contained none of the substance.

Oxygen absorption :2? test, 000, 10cc.

sample/l5 minutes 031 (blank) sample .50 100 011+2% (0H,): Sm (C0135);.32 7-1o11-1o 5 The cone deposit test is conducted by passing the oil ata definite rate through a groove cut in the inner surface of a steelcone of standardized dimensions, held at a temperature of 250 0.

The deposit represents the sum of the solids deposited on the cone andfound suspended in the oil after passing therethrough. The numeralrepresents milligrams of insolubles per 60 cc. of oil.

The oxygen absorption test represents the amount of oxygen in cubiccentimeters absorbed during successive 15 minute intervals where oxygenis conducted in a closed circuit, bubbling through 10 cc. of oil, whichis maintained at a temperature of 200 C. From these tests it will beobserved that the presence of the particular tin compound reduced theamount of the cone deposit very materially and greatly reduced the rateat which oxygen was absorbed.

A wide variety of other compounds are equally satisfactory, among whichmay be mentionedhexaphenyl tin, tetracresyl bismuth, tetramethylmercury, hexaphenyl lead, trimethyl tin triphenyl lead, triethyl tindiphenyl bismuth, tripropyl tin dicresyl antimony, dinaphthyl bismuthdicresyl arsenic, diisopropyl tin diphenyl bismuth dicresyl arsenic andtrimethyl tin diphenyl thallium.

The present invention is not limited to any theory of the action ofmetallo organic agents ,nor to any particular agent or metallo element,

but only to the following claims in which it is desired to claim allnovelty inherent in the invention.

I claim:

1. An improved lubricant comprising a hydrocarbon lubricating oil and anoil soluble metallo organic compound containing at least two but notmore than three metal atoms selected from the 2nd, 3rd, 4th and 5thgroups of the periodic system, two of said metal atoms being linkedtogether in the molecule and directly attached to at least one carbonatom.

2. An improved lubricant comprising a hydrocarbon lubricating oil and anoil soluble metallo organic compound containing at least two but notmore than three metal atoms selected from the 2nd, 3rd, 4th and 5thgroups of the periodic system, two of said metal atoms being linkedtogether, at least one of which is an atom of tin, said atoms beingdirectly attached to at least one carbon atom.

3. Composition according to claim 2 in which the metallo-organiccompound contains two metal atoms at least one of which is an atom oftin.

4. A composition according to claim 2 in which the metallo-organiccompound contains two atoms of tin.

5. An improved lubricant comprising a hydrocarbon lubricating'oil and anoil soluble metallo organic compound containing at least two but notmore than three metal atoms selected from the 2nd, 3rd, 4th and 5thgroups'of the periodic system, two of said metal atoms being linkedtogether, at least one of which is an atom of bismuth, said atoms beingdirectly attached to at least one carbon atom.

5. Composition according to claim 5 containing two metal atoms at leastone of which is an atom of bismuth.

7. Composition according toclaim 5 in which the metallo-organic compoundcontains two atoms of bismuth. I

8. Composition according to claim 5 in which the metallo-organiccompound is tetrecresyl bismuth.

9. An improved lubricant comprising a hydrocarbon lubricating oil and anoil soluble metallo organic compound containing at least two but notmore. than three metal atoms selected from the 2nd, 3rd, 4th and 5thgroups of the periodic system, two 01 said metal atoms being linked U11. Composition according to claim 9 in which together, at least one ofwhich is an atom 01 the metallo-organic compound is tetremethyl mercury,said atoms being directly attached tomercury.

at least one carbon atom. 12. A lubricating oil containing a smallamount 7 10. Composition according 'to claim 9 'containoi trimethyltriphenyl stannane.

in: two metal atoms at least one of which is an v atom of mercury.RAPHAEL ROSEN.

